Manufacture of staybolts for boilers



J. R. FLANNERY.

MANUFACTURE 0F STAYBOLTS FOR BOILERS.

APPucATloN FILED MAR.1,1919.

1,3362 13. Patented Apr. 6, 1920.

y narran sra'rns rar T OFFICE.

ASSIGNOR TO FLNNERY ANIA.

El, PENNS L MANUFACTURE OF STAYBOLTS FOR BOILERS.

Specification of Letters Patent.

Patented Apr. 6, 1920.

Application filed March l, 1919. Serial No. 280,113.

To all whom t may concern:

Be it known that I, Jon'n Bocinas FLAN- NERY, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in the lvfanufacture of Staybolts for Boilers; and l do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled inthe art to which it appertains to make and use the same.

This invention relates to an improvement in the manufacture of stay bolts for boilers and more particularly such as are known as flexible staybolts, the object of the invention being to produce a staybolt from a solid bar of metal and to provide such a bar with a forged head at one end and a drilled tell-tale hole extending continuously from the inner eno of the bolt and terminating in the headed outer end of the bolt, whereby breakage of the bolt at any point between the head and the inner end of the bolt will expose the tell-tale hole and permit the entrance of water for indicating the fracture of the bolt.

Heretofore, it has been proposed to manufacture staybolts having short tell-tale holes extending through the headed ends of the bolts and terminating a comparatively short distance from the head.

It has also been proposed to employ a tubular bar comprising two grooved members welded together, and to upset one end of such a tubular bar to form a head, but when such a method has been followed in the manufacture of a flexible staybolt, it has been dificult to obtain such welding surfaces as will insure a perfect welded connection between the two parts, and consequently when a head is forged at one end of such a tubular bar, the welded connection is liable to open. Furthermore, when a head is forged on the en-d of a tubular bar, the bore will be closed for a prohibitive distance inwardly from the head and the efficiency of such bore as a tell-tale hole will be destroyed.

My invention aims to obviate the various objections and defects heretofore encountered and consists in certain novel features in the manufacture of staybolts for boilers as hereinafter set forth and pointed out in the claims.

lIn the accompanying drawings; Figure l is a view of the blank or solid bar from which the staybolt is made; lFig. 2 is a View showing the head forged at one end of said blank or solid bar; llig. 3 is a sectional view of the completed bolt; F a and 5 are views illustrating a machine whereby the drilling of the tell-tale hole in the solid bar may be effected, Fig. 6 is a cross section of the drilling tool, and Fig. 7 is a detail sectional view showing a portion of the machine.

l represents a solid bar of metal suitable for the manufacture of a flexible staybolt la such as shown in Fig. 3. @ne end of this solid bar is first subjected to the action of forging dies l" whereby the metal will be upset and caused to form a forged head 2. The head may be so shaped as to afford a bearing face such as is provided in the construction of flexible staybolts. In the drawing, the forged head 2 is shown as being spherical but said head may have a different configuration without departing from the spirit of my invention.

After the head shall have been forged at one end of the bolt, a tell-tale hole is drilled in the bolt continuously through the body of the bolt from the other end thereof and terminating its outer end within the forged head of the bolt or in lthe zone of the headed end of the bolt. Tha-t is to say the termination of the tell-tale hole at the headed end of the bolt is such that in the event that the bolt should break at the j uncture of the head with the body of the bolt, the tell-tale hole would be exposed.

My invention provides a staybolt for boilers having a tell-tale hole extending throughout the body of the bolt, so that should the bolt breakat any point between the boiler sheets, water will be permitted to enter the tell-tale hole and denote the broken condition of the bolt.

Staybolts for boilers vary in lengtlnwin some instances being as long as thirty-six inches. Tell-tale holes can be drilled longitudinally through the body of thc bolt from the inner end thereof to and into the forged head at the outer end, successfully, economically and rapidly with the use of mechanism such, for example, as illustrated in Figs. 4, 5 and 6 of thedrawings, but I do not claim herein, the said mechanism as a part of my present invention. The

construction and operation of said mechanism will now be described.

3 are parallel guides preferably cylindrical in shape, and connected by the cross bars 4-5 and 6, the said guides and cross bars forming the frame of the machine which latter is supported on a suitable base or by other means not shown.

Threaded into the bottom cross bar 6, and extending downwardly from the latter is the hydraulic cylinder 7, which is supplied with oil from a pumping system or pressure reservoir through the three-way valve 8 carried by the cross head 6. Located within the Vcylinder 7 and projecting upwardly through a stuffing box 9 screwed into the upper face of the cross head, is the ram 10. This ram is hollow throughout its length and is secured to and carries at its upper end the cross head 11, which is slidably mounted on the guides 3, renewable bushings 12 being provided for taking the wear.

Screwed or otherwise secured to the upper side of cross head 11 is the hollow coupling block 13, into which is inserted and secured by soldering or otherwise, the single flute drill 14. This drill has an oil passage extending throughout its length, and the cross head 11 has a passage connecting the Yupper end of the hollow ram 10 and the lower end of the drill, so that a kportion of the oil which actuates the ram passes up into and through the drill for lubricating its upper cutting edge and also for washing out the chips, the pressure and flow of the oil passing up through the drill being regulated by the stop valve 15 in the cross head 11.

Cross bar 5 is rigidly secured at its ends tothe guides 3 and is provided centrally with a bronze block 18 carrying the drill bushing 16 in which the upper end of the drill 14 normally rests when the cross head 11 is invits lowest position, the lower end of the bushing being counterbored as at 16a A to form a housing for the cutting end of the drill whenthe latter is in its lowest position. The upper end of the bushing 16 forms a center bearing for the small or inner end ofthe stay bolt 1a, which latter is provided with centering recess to receive said center bearing, and it and the housing 16a form a discharge spout leading to the receiving chamber 20, for the oil and cuttings.

Located below the cross bar 5 is the supporting plate 19 preferably secured to the guide 3, by set screws, not shown. This plate carries the receiving chamber 20.which embracesl the lower end of the bushing 16,

Yandwhich receives the waste oil and. chips .as the latter fall from the drill. vber 20 is provided with a spill pipe 21 The chamadapted to discharge the oil and chips into a suitable receptacle placed to receive the same. y v

22 is a cross head located above cross bar 5, and mounted at its ends on the guides 3, the ends of the cross head being split as shown, and provided with clamping screws 23 for clamping it solidly to the guides. Located centrally in the cross head 22 is the bronze bushing 23a in which the bolt driver 24 is mounted to rotate, the end thrust of the bolt and driver being.V taken up by the ball bearing 25 interposed between the lower headed endv of the bolt driver and the adjacent parts of the bushing 23 and the cross head 22. The bolt driver 24 is provided at its lower end with the blade 26 which enters the driver slot in the head of bolt 1, and is threaded at its upper end into a coupling 27 secured to the lower end of the square shaft 28.` This square shaft passes upwardly through a similarly shaped opening in the collar 29 which is threaded to or otherwise secured to the hollow shaft 30,

which latter is mounted in the bushing 31 secured within the upper cross bar 4, and is 'provided above said cross bar with a collar Y36 spaced at short intervals apart whereby it may be adjusted with relation to the lever 34'to accommodate bolts of any length within the limits of the machine.

Secured to the hollow shaft 30 above cross bar 4 is the friction cone 37 which ywith the belt pulley 38, which is recessed to receive the cone, forms a friction clutch for the shaft 30. Thepulley 38 runs freely on the Vshaft 30,-and is normally helddown onto the coneY 37 by the spring 39 interposed between theV collar 40 on shaft 30',l .and the anti-friction bearing 41 against which the hub of the pulley 38 bears. The hub of the pulley is grooved to receive the pins l42 on lever 4 3, which is pivoted on bracket 44 securedto cross Vbar 4, and connected yatV its outer end to a treadle,rnot shown, by a suitable'rod. or pitman.

Bracket 44 also carries the belt pulleys 45 v(only one being shown) around which the belt passes to change the direction of the drive. i v

Located between cross bar 5 and cross head 6, are the drill supports 46 which normally rest on the seats 47 formed on thevertical guides 3, and support the drill' against lateral deflection at points intermediate its length and between the hydraulic lifting means and the bolt being drilled. As the cross head 11 ascends it engages the underside of the lower support 46 and lifts it, and if the upward movement be continued, the upper support 46 will be engaged by the lower support and lifted in a similar' manner. As the drill descends the supports descend with it until their respective seats are reached where they are stopped :and remain until again lifted by the upward movement of cross head 11.

Supporting plate 19 carrying the oil and chip receptacle 20, is provided in its bottom with a key 48, which fits in the flute in the drill and checks the tendency of the drill to twist and also prevents excessive leakage of oil.

In the operation of the machine the bolt 17 to be drilled, after having been center drilled at its shank end, is placed head up on the center bearing 16, the recess in the lower end of the bolt receiving the said center bearing. lf necessary the cross head 22 is elevated by depressing the long end of lever 34, and the bolt moved to the center line of the machine, after which the cross head 22 is lowered until the blade 26 of the driver rests within the driver slot in the bolt head. rEhe cross head 22 is then clamped to the guides 3.

After the bolt has been placed in position retary motion is imparted to the square shaft through the clutch and belt mechanism described, thus rotating the bolt 17 on the center bearing 16. @il is now admitted under `pressure to cylinder 7 and operates to lift the ram 10 and drill 14. rlhe drill is guided and supported in its upward movement and after passing through the bore cf the center bearing 16, which also supports it, it enters the holt and will drill the tell` tale hole continuously from the inner end thereof to and into the forged head, regardless of the length of the bolt. Part of the oil entering cylinder 7 passes up through the rain and bore in the drill and emerges at the point of the latter, thus not only keeping the drill continuously lubricated, but also hy its flow operating to wash out the chips, which, passing down the flute of the drill are discharged into the receiver 20, the flow oil through the drill being regulated as previously explained by the valve 15.

ifte the hole has been drilled, the threeway valve 8 is manipulated to permit the oil to escape from the cylinder 7 thus permitting the ram l() and drill 14 to descend by gravity.

After the bore has been completed the frirtion clutch S8-37 is opened by depressing a treadle (not shown) linked to the lever 43, thus stopping the rotation of the shaft 2S and the bolt 17 connected thereto. The holt 17 is disengaged by releasing the clamp on cross head 22, thus permitting the latter to be elevated by the lever 34 a distance sullicient to release the bolt 17 which is then removed and another placed in position for drilling.

ll'it. this construction it will be seen that the drill, which is comparatively slender, is supported against lateral deflection or bending, at intervals throughout its length during the entire drilling operation, and is also supported adjacent the lower end of the holt, by the key 48 against torsional or twisting stresses, so that the only part of the d ll t at is subjected to torsional stresses ie part above the key.

lt s the intention to provide each machine with a series of units constructed as above desribed, but as they are alike it is unne:` ssary to illustrate more than a single unit.

llavin fully described my invention what l cla in as new and desire to secure by Letters-Fatent, is

rilhe herein described method of making a staybolt for boilers, consistinfr in forging a head on one end of a bar of metal and then drilling a longitudinal tell-tale hole in air b `r and terminating said hole within die headed end thereof.

The herein described method of making staybolt for boilers, consisting in first a head on one end of a bar of metal, then drilling tell-tale hole longitudi- Y 'n said bar from the inner end thereand terminating said hole within the bar in the Zone of the headed end thereof. v

3. rEhe herein described method of making a flexible staybolt for boilers, consisting in nrst forging rounded head at one end of a solid bar of metal, and then drilling a hele longitudinally in said bar from the inner end thereof and terminating said telltale hole within the rounded head at the outer end of the bar.

4. A staybolt for boilers made in a single piece having a forged head at its outer end and having lrilled tell-tale hole extending continuously through the body of the bolt from the inner end thereof and terminating within the forged head at the outer end of the bolt.

ln testimony whereof, I have signed this specification in the presence of two subscribing witnesses.

JOHN ROGERS FLANNERY. lllitnesses JAs. R. HoRAN, F. H. ALLIsoN. 

